Remove the engine's aluminum coating

Polishing is a LOT of work.
I think it's why so many guys just shoot black paint onto old aluminum. <G>
 
We never covered that in chemistry! Admittedly, oven cleaner doesn't yield the best results but most people have it in the kitchen and it's worked for me in the past. I spray it on a and wipe it off with the clearcoat. A quick soapy dunk and rinse after. All my covers are scored so I use 240, 600, then 1000 before I buff. I emery the hell out of it then use autosol on the loose buff. Your shine job is awesome but I stop at the results below...just don't have the patience.
 

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I fully agree with ADC's advice - the mirror-like results speak for themselves. Beautiful work. My still-in-progress bike looks great but it's just not a showpiece. Here's how it looked during the second round of changes:

cb-header.jpg


Here's what the other side looks like now:

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I used aluminum stripper to remove the clear coat. In a few spots I had to do it a second time. I used 500 then 1000 grit wet sandpaper with a block underneath to erase the surface scratches. Then I went around with an electric drill set of little polishing wheels - the cone-shaped one worked the best. The kit came with two grades of compound. One at a time I pulled an allen-head bolt, polished around it, then replaced it. The final step was a good hand-polish with Mothers aluminum polish. It's not perfect by any means but it sure looks better than what I had.

Thanks again to ADC.

If anyone is interested in seeing more about my bike, check it out here: http://www.projectvf.com/cb360.htm Please note the black-painted stock exhausts have been replaced by a vintage header.
 
Sorry man... not trying to rain on your parade here, but that job looks a bit rushed. You can make out a lot of scratches still there. It looks tons better, to be sure, but it's a ways off from being considered "polished".

500 grit is way too fine as a starting point and 1000 grit is much too bit of a jump from 500 grit.

You have to go step-by-step like ADC was saying. For my alternator I went through 220, 320, 400, 600, 800, and then 1000 grit paper. Wet sanding each time until the marks from the previous had been removed. I probably sanded for 15-20 minutes through each grade and the whole process took my about three hours.

Here's the starting point:
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Even after the 220 grit, things looked bad:
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This is just after finishing in the 1000 grit, getting ready for buffing:
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And here's after brown tripoli on the buffing wheel (I skipped the black emery):
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And this still isn't a "show quality" finish. I didn't have a spare flannel wheel to use with the rouge for a true mirror finish, but at this stage you can also use a chemical polish like mother's along with a microfiber cloth.
 
<<500 grit is way too fine as a starting point and 1000 grit is much too bit of a jump from 500 grit.>>

Absolutely true.
It does not save time to skip grits. It takes more time and yield poorer results.

For now, I think he accomplished what he set out to do. It can always be polished, or brushed, or whatever in the future. As for me, I can't seem to stop myself until I see myself. <G>

I have sets of wheels and buffs for each grade of polishing compound that I have, so it is just a quick wheel change when I go to another compound, but you can use a hack saw blade or something as a rake to clean the buffing wheel before going to the next finer compound. Not quite as good as changing the wheel, but it will usually suffice.
 
Sonreir said:
Sorry man... not trying to rain on your parade here, but that job looks a bit rushed. You can make out a lot of scratches still there. It looks tons better, to be sure, but it's a ways off from being considered "polished".
Don't worry about the rain. My tattered umbrella shields me from most of it. :)

The existing finish is about as far as I want to go. It's not perfect but much better than what I started with. When you look at the old gouges and scrapes, the surface scratches are hardly noticeable. If you go back thru my posts you can see I'm not looking for mirror quality. Doing just the side covers without doing the entire engine to match would look pretty odd and I simply don't have the time for everything, especially with the fork lowers and rear hub yet to go.

When you're doing any sort of custom work you have to decide how deep down the rabbit hole you want to dive. For now I'm happy with the results. I went from a t-shirt to a low-cost suit, so maybe later I'll upgrade to Brooks Brothers.
 
Definitely. I didn't polish my cases, either. I just did the alternator cover and called it a day. I ended up painting the rest in metallic paint and it looks OK.
 
With the exception of the outer cases, aren't those engines painted silver?
 
I like your polish job. they look better. The mirror finish is too much work the keep. Every time you finish a ride you will have to go out and polish them to get off the sand blast scratches from doing 80 in a school zone.

But I would go back to 250 on those deep gouges. You should be able to remove them completely. then take the polish as far as you want.
But if you want to hide them some, you can use a fine brass wire brush on them. you will still have to re-polish the surrounding area after.
 
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